Ensuring that a product has not been tampered with after being packaged can be of considerable importance, and especially so for products intended for human consumption, such as food, drink and pharmaceutical products.
It is therefore advantageous to be able to provide packaged products with tamper evident means.
An example of where this may be of particular importance is the bulk packaging of food products, which often undergo further processing by the recipient of the product.
For example, powdered or particulate food products such as flour and milk powder are usually bulk-packaged within large 25 kg bags. The recipient of such bulk packaged products will want to ensure that each package has not been tampered with prior to its arrival and/or prior to the further processing of the product. The further processing may, for example, include blending the bulk packaged product in with other ingredients and/or subsequently repackaging the product into smaller packages. If subsequent tests showed that the blended product and/or repackaged product contained impurities, but that the bulk packaged product arrived with no evidence of it having been tampered with, then the bulk packaged product may be disregarded as the possible source of the contamination. This would not only serve to exonerate the product manufacturer, but it would be useful in helping to narrow down the possible source of the contamination.
It would therefore be advantageous if there was available a means of providing bulk packaged food products with tamper evident means.
An example of a tamper evident means for use with the packaging of products is described in NZ Patent No. 531014. This patent describes a system for vacuum packaging a product within bags, for example general food products or milk powders. The system described is effective in showing if the contents of any one bag have been tampered with, because the tampered bag would lose its vacuum, and this would therefore be apparent to the person or company receiving or using the bag.
However, the technology described in NZ Patent No. 531014 (whilst usually effective) is somewhat complex, and the machinery required to produce the vacuums is reasonably large, and expensive. This may be prohibitive to some companies wishing to use the technology. Furthermore, the procedure of forming a vacuum in each and every bag may take a reasonable amount of time, and this may therefore reduce the speed or operating capacity of the packaging line.
It would be advantageous therefore if there was available an alternative tamper evident means for use with the packaging of products.
There are many examples in the prior art of tamper evident means for use with the packaging of valuable or important items such as money, documents or forensic evidence. Examples of such tamper evident technologies include: the use of points of weakness in the packaging material; microdot markers; UV fluorescent dies; tamper evident adhesives—and combinations of these technologies. Examples may be found in the following patent documents: U.S. Pat. Nos. 7,095,324, 4,509,196, 7,008,106, 4,464,158, 6,962,439 and DE4017759A1.
However, whilst these tamper evident technologies may be effective to some degree, they do not also offer a product security means for validating the authenticity of the packaged product.
As a result, product security technologies for use with packaging have emerged, most notably devices such as holograms or Optically Variable Devices (OVD). OVD's are usually attached to packaging materials by the use of adhesives, for example by hot foil stamping or by the use of pre-applied adhesives stuck to a carrier film.
Examples of the use (or manufacture) of OVD's for packaging may be found in the following patent documents: U.S. Pat. Nos. 5,913,543, 6,975,765, 7,095,324 and 4,758,296.
However, a disadvantage associated with the use of OVD's is that they may be susceptible to being removed from the packaging material, for example by the use of solvents to weaken the adhesives. In such instances, they may then be reapplied to a counterfeit or tampered product.
Alternatively, OVD's may be cut from the packaging material and removed, before being reapplied to a counterfeit or tampered product.
Another disadvantage associated with the use of OVD's is that they do not usually provide, or offer, tamper evident means. That is, the presence of an OVD may indicate that the packaged product is genuine, however the OVD may not be able to also indicate whether or not the packaged product (or the OVD itself) has been tampered with. Hence, if a packaged product (or OVD) has been tampered with, without destroying the integrity of the packaging (or the OVD), then the end user may be none the wiser.
It would be of advantage therefore if there was available packaging which included a product security means which may also serve as a tamper evident means.
It is an object of the present invention to provide packaging methods and apparatus which go some way towards addressing the aforementioned problems or difficulties, or which at the very least provides the public with a useful choice.